I have an area that is currently coverd in a a mix of patchy grass and weeds which I'd like to replace with a alternate groundcovers. I'm thinking of using creeping thyme, corsican mint or maybe cottoneaster. Thing is, I don't want to clear the entire area and plant it, I'm hoping that I can add a few plants and let them slowly take over the area. I'm wondering if that can be done and if so, the best way to do it? The 3 options I can think of are (in order of ease): 1. Simply plant among the vegetation. 2. Kill the vegetation in an area and then plant. 3. Dig up an area and plant. If I do dig up an area, is it best to surround the plants with mulch (I'm thinking of bark mulch) or should I leave the plants surrounded with bare ground to take over? Thanks.